I am more than thrilled to share this beautiful and utterly delicious strawberry mousse cake recipe with you today. I am so, so, so happy with my latest strawberry cake creation and I have a feeling that I will chose this cake as my favorite summer cake at the end of this summer.
Ever since strawberries popped up at the farmers' market a few weeks ago I was brainstorming what kind of new cake creation I could make that involves strawberries. Last year I shared this classic French strawberry tartlet recipe with you but this year I wanted to share something different. I think you are not surprised that a strawberry mousse was the first thing that came to my mind; you know how much I like mousse cakes. The next question that kept me busy was " how to pair the strawberry flavor". I wanted the strawberry flavor to be the main flavor and to be honest I was a little bit lost how to pair the strawberry flavor. One day I was cooking with lemongrass which I do quite often besides using kaffir lime leaves (it is a delicious pairing with fish) and then I suddenly knew that lemongrass and strawberry were the perfect match.


When I made my first trial cakes  I was not entirely convinced if this was the dream flavor match because I never ate this flavor combination and I am always willing to try new things. My worries were totally unnecessary because my first intuition was right. Indeed strawberry and lemongrass is a wonderful flavor combination and I like it a lot. However, I had to made three more cake trials until I got the balance right. The lemongrass flavor was too strong - for my taste -  in my first trials.
The next obstacle  that I had to overcome was the bottom of the cake. In my first trials I used a almond sponge cake but I was not entirely happy with it. It was too soft for my taste and I wanted to have a cake bottom with a little bit of crunch but I could not make up my mind which shortcrust pastry I should make. After several attempts I decided on a sablé Breton but I used less salt than a classic sablé Breton dough.
So here I am presenting you my strawberry mousse cake with a lemongrass mousse and strawberry jelly core, a crunchy sablé Breton bottom and strawberry glaze. 
I am aware that this cake recipe takes a little bit of time bur I promise it is worth the preparation time. I strongly recommend reading through the recipe before start baking and as I always say you do not have to make the cake on one single day but over the course of a few days.
Happy baking and enjoy this delicious strawberry season!


Makes 12 strawberry mousse cakes ( 7 cm / 2.75 inches in diameter)

Lemongrass Mousse Core

  • 20 g /2 stalks of fresh lemongrass
  • 20 g / 1 1/2 tablespoons granulated sugar
  • 70 g / 1 /4 cup and 1 tablespoon heavy cream
  • 1 sheet gelatin (1.5 g), soaked
  • 5 ml / 1 teaspoon freshly squeezed lemon juice
  • 85 g / 1 /3 cup heavy cream
  • Clean the stalks of lemongrass. In order to free the aromatic oils of the lemongrass bruise the stalks. Smash the stalks with a cleaver or the like. Then cut the bruised lemongrass stalks into pieces. 
  • Pour the heavy cream into a small pot and add the granulated sugar and the lemongrass to the heavy cream. Bring the mixture to a boil. Set the pot aside and cover the pot with a lit and let the mixture steep for ten minutes. Strain the mixture through a sieve, make sure you do not have any lemongrass pieces left in the heavy cream mixture. Pour the mixture back into the pot and bring it almost to boil. Set aside and add the soaked gelatin sheet. Mix until the gelatin is completely dissolved. Pour the mixture into a medium sized bowl and let it cool down to room temperature. Add the lemon juice and mix well. 
  • In the meantime whip the heavy cream until creamy. Fold in the whipped cream into the flavoured lemongrass mixture.
  • Evenly distribute the lemongrass mousse into 12 small (silicon) moulds (2.5 cm / 1 inch in diameter; the height is 2.5 cm / 1 inch). Freeze the moulds for at least 1 1/2 hours. Meanwhile you can make the strawberry puree. 

Strawberry Puree

  • 750 g / 3 1/2 cups fresh strawberries
  • 70 / 1/3 cup granulated sugar
  • Wash strawberries and remove the leavy tops of the strawberries. Quarter big strawberries and half smaller strawberries. Place the strawberries and the granulated sugar in a big pot ( do not add any water) and let the mixture cook over medium. Let it simmer until the strawberries are soft which takes about 10 minutes. Remove the strawberry mixture from the heat and let it cool for a few minutes, Puree the strawberry mixture; strain the mixture through a fine sieve. Let the puree cool completely. You can keep the strawberry puree for a few days in the fridge.

Strawberry Jelly

  • 170 g / 2/3 cup and 1 tablespoon strawberry puree
  • 1 1/3 sheets gelatin (2 g), soaked
  • Slowly heat 1/3 of the strawberry puree in a small pot. Set the pot aside and dissolve the gelatin in the warm strawberry puree. Pour the warm strawberry puree to the rest of the puree and mix well. Evenly distribute the strawberry jelly on the frozen lemongrass mousse. Freeze the moulds again for at least 1 hour. 

Strawberry Mousse

  • 100 g / 1/3 cup and 1 tablespoon heavy cream
  • 2 2/3 sheets gelatin (4 g)
  • 30 g /1 ounce white chocolate, finely chopped
  • 150 g / 2/3 cup strawberry puree
  • 250 g / 1 cup and 1 tablespoon heavy cream
  • Pour the the heavy cream into a small pot and bring it almost to a boil. Set the pot aside and dissolve the gelatin in the hot heavy cream. Add the chopped white chocolate and stir again until the chocolate is completely melted. Then add the strawberry puree and mix again. Pour the mixture into a medium sized bowl and let it cool until it has reached room temperature. 
  • Whip the heavy cream creamy. As soon as the strawberry mixture has cooled to room temperature fold in the heavy cream. 
  • Place hemisphere moulds ( 7 cm / 2.75 inches in diameter) onto board or a flat plate. Fill the moulds 2 /3 with the strawberry mousse. Unmould the frozen lemongrass strawberry cores and gently press the frozen cores into the strawberry mousse. Freeze the mousse cakes for at least 6 hours or overnight, You can keep the frozen hemisphere moulds for a few weeks in the freezer. 

Sablé Breton Bottoms

  • 150 g / 2 2/3 sticks unsalted butter, soft
  • 150 g / 3/4 cup granulated sugar
  • 60 g egg yolks / equals egg yolk of 4 medium sized eggs
  • 200 g / 2 cups pastry flour
  • 4 g / 1 teaspoon baking powder
  • 1 pinch of salt
  • Preheat the oven to 170 °C/ 340 °F. Line a baking sheet with parchment paper. 
  • Mix the soft butter and the granulated sugar with a (wooden) spoon. Add the egg yolks to the mixture and stir until well incorporated. 
  • Mix flour, baking powder and salt in a separate bowl. Add the flour mixture to the butter egg mixture and stir again well. 
  • Spread the batter onto the lined baking sheet. Bake the sablé Breton for 17 minutes. Remove the baking sheet from the oven. Cut out circles with a cookie cutter. Place the baking sheet back into the oven and bake the cookie disks for another 5 to 7 minutes until they are golden brown in color. Remove the discs from the baking sheet and let the cookies cool on a wire rack. 
  • I recommend making the sablé Breton on the day of assembling the cake because the sablé Breton cookies stay crunchy for a day; the next day the cookies get soft. 

Strawberry Glaze

  • 90 g / 1/3 cup and 1 tablespoon strawberry puree
  • 50 g / 3 1/2 tablespoons simple syrup *
  • 2 2/3 sheets of gelatin (4 g), soaked
  • Place the strawberry puree and the sugar syrup in a pot and bring the mixture almost to a boil. Set the pot aside and dissolve the gelatin in the hot mixture. Pour the mixture into a jug (this way it is the easiest to pour the glaze over the mousse cakes). Let the glaze cool to almost room temperature and then glaze the mousse cakes. Make sure that the glaze has room temperature when glazing the cakes. If the glaze is too hot you will realize that the glaze will be too runny. 
  • If you do not use the glaze right away pour the glaze into a jar, let it cool completely, then store the jar in the fridge up to 5 days. Carefully reheat the strawberry glaze. 
* This is how you make a simple syrup: Place 90 g / 1/3 cup and 1 tablespoon granulated sugar and 65 g / 1/4 cup water in a pot. Bring the mixture to a boil and let it boil until the granulated sugar is completely dissolved. Let it cool down to room temperature. You can store the simple syrup in the fridge up to two weeks (store it in a sealed jar).

Assembling

  • 12 halved medium sized strawberries, for decoration
  • Unmould the frozen mousse cakes and place the cakes on a wire rack. Place a deep plate under the wire rack, so you can catch the excess strawberry glaze and reuse the glaze.
  • Pour the glaze over the frozen mousse cakes, let the glaze set for a few seconds, then carefully remove the cakes from the wire rack (I use a food turner) and place the glazed hemisphere cake on a sablé Breton disc. If the glaze gets too thick, place the glaze back into the pot and gently reheat the glaze. 
  • I recommend not glazing all the mousse cakes at once. I usually glaze five mousse cakes at a time because then I can make sure that the mousse cakes are completely frozen while glazing.
  • Place each mousse cake on a cake board and decorate the cakes with half a strawberry. Let the strawberry cakes defrost in the fridge which takes about 1 1/2 hours.
  • Keep the cakes in the fridge until consumption. I recommend eating the cake on the same day you assembled the cake because otherwise the sablé Breton bottoms get soft.